VLF法预报“神舟二号”发射期间的太阳活动情况  

Forecast on solar activity during the launch of“Shenzhou Ⅱ”by the VLF method

作　　者：牛有田[1,2] 张优贤 谢迎涛 李丹丹[1] 李玲[1] 

机构地区：[1]河南师范大学物理与电子工程学院,新乡453007 [2]河南省光伏材料重点实验室,新乡453007

出　　处：《地球物理学进展》2014年第3期1426-1430,共5页Progress in Geophysics

基　　金：国家自然科学基金项目(49070217)资助

摘　　要：太阳耀斑是最剧烈的太阳活动之一.当太阳耀斑爆发时,辐射出的X射线会引起甚低频信号的相位异常变化.在河南新乡用甚低频接收仪监测了2001年1月10日"神舟二号"发射期间的甚低频信号相位异常数据,并对监测到的甚低频信号相位异常变化量进行了分析和一系列的处理,反演了太阳耀斑的强度和级别,并与美国的GOES卫星观测的结果进行了比较,研究结果表明:预测数据吻合恰好,验证了此法的可行性,为进一步开展我国电离层天阳活动预警和预报奠定了观测基础.Solar flare is the most intense solar activity.Very low frequency（VLF）signals spread through the waveguide between the ground and the low ionosphere.When a solar flare bursts,the suddenly increasing of low ionosphere D layer electron concentration and the equivalent reflection height reducing will cause a sudden ionosphere disturbance,and lead to the spread of VLF phase anomalies.In this paper,VLF signals are collected by the VLF signal receiver based on software radio technology by single whip antenna,receiving Russian Alpha VLF signals of VLF radio navigation system,Rb Atomic Frequency Reference is considered as the local frequency standard of the receiver for it provides sine wave which has precision above 1×10-11 MHz.It is used to produce A/D sampling pulse signal of software radio VLF receiver,phase measurement accuracy of this system is ±1μs.VLF receiver monitored the solar activity in Xin-xiang,He-nan province on January 10,2001 when ＂Shenzhou II＂ was launched,then,we fitting to solve the relationship equation between the flux density and the reducing value of the ionosphere＇s height of the sun＇s X-ray.We use the least square method to take a fitting for the phase anomaly data,at the same time,we forecast the strength of the solar flares,and the predicted results is the same as the observation of the GOES satellite of America,thus verifying the feasibility of the method.The above results illustrate that VLF method can be used in the investigation of the ionospheric solar activity,and serve as the observational basement of the solar activity nowcasting and forecasting technique.

关 键 词：甚低频 电离层 太阳活动 X射线 相位异常 

分 类 号：P172[天文地球—天文学]